Abstract: The oxidation activity of CuO supported on CeO₂ and Al₂O₃ was investigated using the oxidation of carbon monoxide as a model reaction. The reducibility and Cu oxide species of the catalysts were studied by XRD and TPR techniques. The susceptibility of COto oxidation strongly depends on the support: the catalytic activity of CuO/CeO₂ is much higher than that of CuO/Al₂O₃. It is found that the existing forms of copper species, crystal particle size of CuO, the reducibility and activity of catalysts are affected by thermal treatment. The formation of CuAl₂O₄ spinal species at high temperature is the main reason for activity decrease of CuO/Al₂O₃ catalyst, and the increase of crystal particle size of CuOis the main reason for activity decrease of CuO/CeO₂.

Key words: CuO/CeO₂, CuO/Al₂O₃, catalyst, reducibility, oxidation activity